Piero Marone

Prevalence of and risk factors for fungal vaginitis caused by non-albicans species

OBJECTIVE Our purpose was to evaluate the prevalence of symptomatic yeast vaginitis caused by non-albicans species among patients attending a vaginitis clinic over an 8-year period. STUDY DESIGN A retrospective study of 1263 patients with symptomatic yeast vaginitis confirmed by culture techniques was performed. RESULTS The prevalence of symptomatic fungal vaginitis caused by non-albicans species increased from 9.9% (10/101) in 1988 to 17.2% (36/209) in 1995 (chi 2 for trend = 9.33, p = 0.002). Non-albicans species were found more frequently in known human immunodeficiency virus-seropositive patients (23/102 vs 143/1161, odds ratio 2.07, 95% confidence interval 1.2 to 3.46) than in seronegative subjects or subjects of unknown status for the virus. Recurrent vaginal candidiasis was an additional risk factor for vaginitis caused by non-albicans species (odds ratio 2.47, 95% confidence interval 1.72 to 3.52). The increase in non-albicans isolates during the study period was confirmed in stratified analysis and in the subgroup of self-referred patients with no history of either human immunodeficiency virus infection or recurrent vaginal candidiasis. CONCLUSION The prevalence of fungal vaginitis caused by non-albicans species has increased sharply in the setting of a vaginitis clinic. The characteristics of risk factors suggest that fungal cultures should be done routinely in human immunodeficiency virus-seropositive subjects with suspected vaginal candidiasis and in patients with recurrent vaginal infection.

Paranasal sinus fungus ball: diagnosis and management.

Paranasal sinus fungus ball is an extramucosal mycosis, usually occurring in immunocompetent people as a monolateral lesion. To review the literature data and to report the Policlinico S. Matteo, University of Pavia experience, 81 patients presenting paranasal fungus ball have been treated (January 1994 to May 2005). Twenty‐seven men and 54 women (19–91 years old; mean 49.4 years) were considered. Seventy‐three patients had a single sinus affected, but eight presented multiple localisations. Maxillary was the most involved sinus followed by sphenoidal and ethmoidal. Moulds have been isolated in 28/81 cases. Histology showed fungal colonisation but not invasion in all cases. Tomography showed bone erosion in 33.3% of patients. All have been treated only by functional endoscopic sinus surgery. Seventy‐seven of 81 patients have been cured. Four of 81 patients needed another surgical treatment. Follow up was between 6 and 132 months (average: 63 months). Fungus ball is a sinusal pathology caused by mycetes like Aspergillus spp. Histology confirms the fungal aethiology excluding tissue invasion. Mycological culture consented to identify the pathogenic mould in 34.5% of cases. Actually functional endoscopic sinus surgery is the gold standard for treatment of this pathology, and antifungal therapy is unnecessary.

Management of splenic abscess: report on 16 cases from a single center

OBJECTIVES Splenic abscess is an uncommon disease, with a reported incidence of 0.14-0.7% in autoptic series. The best treatment option remains unclear. We report our experience of percutaneous drainage of splenic abscess under ultrasound (US) guidance. METHODS From 1979 to 2005, 16 consecutive patients (12 male and four female; mean age 39.9 years, range 16-72 years) were diagnosed with splenic abscess by means of US, and were treated with medical therapy alone or combined with US-guided percutaneous aspiration or catheter drainage. RESULTS Ten of 16 patients had bacterial abscesses (including one case of tubercular abscess), two had an amebic abscess, and four had fungal abscesses. Seven of ten patients with bacterial abscesses were successfully treated with fine needle aspiration alone, one patient was successfully treated with fine needle aspiration for one abscess and catheter drainage for another, and one patient, who subsequently required a splenectomy for an abdominal trauma, successfully underwent percutaneous catheter drainage alone. Four patients with fungal lesions were treated with medical therapy alone, and two patients later required a splenectomy. One patient with a bacterial abscess due to endocarditis was treated with medical therapy alone, and his recovery was uneventful. CONCLUSIONS US-guided percutaneous aspiration of splenic abscesses is a safe and effective procedure. It can be used as a bridge to surgery in patients who are critically ill or have several comorbidities. Percutaneous aspiration may allow complete non-operative healing of splenic abscesses or temporize patients at risk for surgery.

Humans parasitized by the hard tick Ixodes ricinus are seropositive to Midichloria mitochondrii: is Midichloria a novel pathogen, or just a marker of tick bite?

Abstract Midichloria mitochondrii is an intracellular bacterium found in the hard tick Ixodes ricinus. In this arthropod, M. mitochondrii is observed in the oocytes and in other cells of the ovary, where the symbiont is present in the cell cytoplasm and inside the mitochondria. No studies have so far investigated whether M. mitochondrii is present in the salivary glands of the tick and whether it is transmitted to vertebrates during the tick blood meal. To address the above issues, we developed a recombinant antigen of M. mitochondrii (to screen human sera) and antibodies against this antigen (for the staining of the symbiont). Using these reagents we show that (i) M. mitochondrii is present in the salivary glands of I. ricinus and that (ii) seropositivity against M. mitochondrii is highly prevalent in humans parasitized by I. ricinus (58%), while it is very low in healthy individuals (1·2%). These results provide evidence that M. mitochondrii is released with the tick saliva and raise the possibility that M. mitochondrii is infectious to vertebrates. Besides this, our study indicates that M. mitochondrii should be regarded as a package of antigens inoculated into the human host during the tick bite. This implies that the immunology of the response toward the saliva of I. ricinus is to be reconsidered on the basis of potential effects of M. mitochondrii and poses the basis for the development of novel markers for investigating the exposure of humans and animals to this tick species.

Antibiotic-Impregnated Fibrin Glue in Ocular Surgery:In vitro Antibacterial Activity

A strategy to reduce postoperative ocular infections might consist in maintaining a high antibiotic concentration in the eye by using a topical slow-release drug formulation. Fibrin glue is widely used in ocular surgery. Vancomycin, teicoplanin, cephalothin and gentamicin were added to a 500 IU/ml thrombin solution, their concentrations in 1 g fibrin glue being 500 µg for vancomycin and 400 µg for the other drugs. The in vitro antibacterial activity of antibiotic-impregnated fibrin glue was evaluated against a recent clinical isolate of Staphylococcus epidermidis. Moreover the antibiotic elution from fibrin discs in saline was assayed for up to 96 h. Fibrin glue properties were maintained when thrombin was reconstituted with a CaCl2 solution additioned with the antibiotics tested. All antibiotic fibrin mixtures exhibited good antistaphylococcal activity immediately after the preparation. A prolonged inhibition (4 days) of S. epidermidis growth was observed with teicoplanin discs. Gentamicin and teicoplanin levels were higher than those of the other antibiotics. The results suggest that the fibrin glycopeptide and/or gentamicin mixtures can be used, both prophylactically and therapeutically, in ocular surgery.

Genomic Epidemiology of Klebsiella pneumoniae in Italy and Novel Insights into the Origin and Global Evolution of Its Resistance to Carbapenem Antibiotics

ABSTRACT Klebsiella pneumoniae is at the forefront of antimicrobial resistance for Gram-negative pathogenic bacteria, as strains resistant to third-generation cephalosporins and carbapenems are widely reported. The worldwide diffusion of these strains is of great concern due to the high morbidity and mortality often associated with K. pneumoniae infections in nosocomial environments. We sequenced the genomes of 89 K. pneumoniae strains isolated in six Italian hospitals. Strains were selected based on antibiotypes, regardless of multilocus sequence type, to obtain a picture of the epidemiology of K. pneumoniae in Italy. Thirty-one strains were carbapenem-resistant K. pneumoniae carbapenemase producers, 29 were resistant to third-generation cephalosporins, and 29 were susceptible to the aforementioned antibiotics. The genomes were compared to all of the sequences available in the databases, obtaining a data set of 319 genomes spanning the known diversity of K. pneumoniae worldwide. Bioinformatic analyses of this global data set allowed us to construct a whole-species phylogeny, to detect patterns of antibiotic resistance distribution, and to date the differentiation between specific clades of interest. Finally, we detected an ∼1.3-Mb recombination that characterizes all of the isolates of clonal complex 258, the most widespread carbapenem-resistant group of K. pneumoniae. The evolution of this complex was modeled, dating the newly detected and the previously reported recombination events. The present study contributes to the understanding of K. pneumoniae evolution, providing novel insights into its global genomic characteristics and drawing a dated epidemiological scenario for this pathogen in Italy.

Kinetics of T-Lymphocyte Subsets and Posttransplant Opportunistic Infections in Heart and Kidney Transplant Recipients

Background. The potential use of T-lymphocyte measurements as infection risk markers after solid organ transplant has not been fully investigated. We analyzed the kinetics of T-lymphocyte subsets within the first 8 months posttransplant and their correlation with opportunistic infections (OIs) in solid organ transplant recipients. Methods. Serial measurement of CD4 and CD8 T cells was performed retrospectively in 48 heart transplant recipients (HTR) and 42 kidney transplant recipients (KTR). Generalized estimating equation models were used to analyze longitudinal data separately for HTR and KTR. Results. An initial CD4 T-cell drop (at months 1 and 2, in HTR and KTR, respectively) coincided with the peak of OIs. HTR with a low nadir CD4 T-cell count (≤200/&mgr;L) showed poor CD4 T-cell recovery (175±277 cells/&mgr;L at baseline vs 242±99 cells/&mgr;L at month 8) and their CD8 T cells increased from 153±194 cells/&mgr;L at baseline to 601±399 cells/&mgr;L at month 8. KTR with a low nadir CD4 T-cell count (≤200/&mgr;L) showed a modest CD4 T-cell recovery (138±46 cells/&mgr;L at baseline vs. 440±448 cells/&mgr;L at month 8), and their CD8 T cells increased from 90±41 cells/&mgr;L at baseline to 450±242 cells/&mgr;L at month 8. HTR developing OIs had lower CD4 (P<0.001) and CD8 T cells (P=0.001) than those without infections, whereas in KTR the risk for OIs seemed restricted to patients with low CD8 T cells. HTR with OIs had a low CD4/CD8 T-cell ratio, whereas KTR had a high CD4/CD8 T-cell ratio. Conclusions. Determination of T-lymphocyte subsets is a simple and effective parameter to identify patients at risk of developing OIs.

Human enterovirus and parechovirus infections in newborns with sepsis-like illness and neurological disorders

Enterovirus (HEV) and parechovirus (HPeV) infections are common in the neonatal period, and account for a large portion of febrile illnesses during the summer season. HEV infections appear clinically and seasonally similar to HPeV infections. In this study, we present the virological and clinical data from neonates infected with HEV or HPeV and hospitalized in a neonatal intensive care unit for sepsis-like illness or neurologic disorders. In the period January 2010 to October 2013, 54 cerebrospinal fluid (CSF) and 10 plasma samples were obtained from 60 newborns aged <30 days. A total of 7/60 (11.6%) patients were positive for HEV infection and 3 (5.0%) were positive for HPeV infection as determined by specific real-time RT-PCR. The most common clinical signs were fever, irritability, hyporeactivity and, in a few cases, rash. All infections were observed during the summer-fall period. In conclusion, HEV and HPeV were shown to account for a significant portion of febrile illnesses in neonates requiring hospitalization.

Tracking Nosocomial Klebsiella pneumoniae Infections and Outbreaks by Whole-Genome Analysis: Small-Scale Italian Scenario within a Single Hospital

ABSTRACT Multidrug-resistant (MDR) Klebsiella pneumoniae is one of the most important causes of nosocomial infections worldwide. After the spread of strains resistant to beta-lactams at the end of the previous century, the diffusion of isolates resistant to carbapenems and colistin is now reducing treatment options and the containment of infections. Carbapenem-resistant K. pneumoniae strains have spread rapidly among Italian hospitals, with four subclades of pandemic clonal group 258 (CG258). Here we show that a single Italian hospital has been invaded by three of these subclades within 27 months, thus replicating on a small scale the “Italian scenario.” We identified a single clone responsible for an epidemic outbreak involving seven patients, and we reconstructed its star-like pattern of diffusion within the intensive care unit. This epidemiological picture was obtained through phylogenomic analysis of 16 carbapenem-resistant K. pneumoniae isolates collected in the hospital during a 27-month period, which were added to a database of 319 genomes representing the available global diversity of K. pneumoniae strains. Phenotypic and molecular assays did not reveal virulence or resistance determinants specific for the outbreak isolates. Other factors, rather than selective advantages, might have caused the outbreak. Finally, analyses allowed us to identify a major subclade of CG258 composed of strains bearing the yersiniabactin virulence factor. Our work demonstrates how the use of combined phenotypic, molecular, and whole-genome sequencing techniques can help to identify quickly and to characterize accurately the spread of MDR pathogens.

Comparison of an improved RAPD fingerprinting with different typing methods for discriminating clinical isolates of Staphylococcus spp.

Different epidemiological markers were used to characterize 2 Staphylococcus epidermidis and 8 Staphylococcus aureus strains isolated from patients with severe infections. We compared random amplified polymorphic DNA (RAPD) fingerprints, biotypes, antibiotic assays, plasmid profiles and chromosomal DNA restriction endonuclease analysis (REA). Data analysis based on numerical taxonomy methods indicates that RAPD and REA give similar results allowing a good discrimination of the two species and of each isolate. The RAPD method is easier and faster than REA, but the reproducibility of RAPD fingerprints obtained in independent experiments can be problematic. We have found simple technical devices to improve the reproducibility of the RAPD procedure which is therefore a very useful tool in epidemiology for identification and characterization of Staphylococcus spp.